Conditional Compilation

oulevon · 02-26-2006, 06:47 PM

Hello,

I heard that you can conditionally compile something with the #ifdef and #endif. How can I do this. I've looked online but can't find anything. Here's what I'm doing:

Code:

#ifdef DEBUG

        printf("inside DEBUG block\n");

#endif

When I compile this with gcc -DEBUG -o test test.c, the statement is never executed. Am I doing something wrong?

Thanks for any help.

paulsm4 · 02-26-2006, 08:09 PM

You're close.

You need "-D" (like you had), and the symbol is "DEBUG". So you were off by one "D":

Quote:

gcc -DDEBUG -o test test.c

You might also wish to consider this alternate syntax:

Code:

#if defined(DEBUG)

        printf("inside DEBUG block\n");

#endif

oulevon · 02-26-2006, 08:12 PM

Thanks again for your help.

paulsm4 · 02-26-2006, 08:21 PM

My pleasure!